Rotary pump and engine



I. B. HART ROTARY PUMP AND ENGINE.

APPLICATION FILED JULY 8,1920.

Patented Feb. 28, 1922.

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PATENT OFFICE.

ASSIGNOB'TO THE RECIP-ROTO ENGINE COMPANY, or sit. LOUIS, MISSOURI, A CORPORATION or DELAWARE.

ROTARY PUMP AND ENGINE.

Specification of Letters Patent. Patented F b. 28 1922 Application filed July 8, 1920. Serial No. 394,704.

To all whom it may concern:

Be it known that I, IRA B. HART, a citizen of the United States of America, a resident a had to the accompanying drawings, formin a part of this specification.

his invention relates to improvements in rotary pumps and engines, and the novel features of the invention are especially adapted for use in rotary pumps. The main object of the invention is to produce a simple and efiicient automatic valve device adapted to prevent free and open communication between the inlet and outlet ports of a pump or engine.

More specifically stated, the particular structure herein described comprises an cecentricall mounted piston and a pivot connecting t e'piston to a rocker arm. The piston moves away from an inlet port and toward an outlet port toprovide for the admission and discharge of fluid, and owing to the peculiar manner in which it is mounted in the cylinder, the piston also swings from an extreme position near the outlet port to an initial position near the inlet port. During the last mentioned movement of the piston, said piston is separated from the circular inner face of the cylinder, and the passage from port 8, to port between piston and cylinder, should be closed to prevent free communication between the ports. The invention therefore includes a simple automatic valve device, preferably a pressure actuated check valve adapted to contact with the piston and cylinder while the piston is passing from one extreme position. to the other, "thereby preventing communication between the inlet and outlet p I Fig. I is a vertical section illustrating the invention applied to a pump.

Fig. II is a section taken approximately through the center of the structure shown in Fig. I, with the piston shown in elevation.

tion dividing the cylinder into two compartments.- Each compartment contains a piston and a rocker arm which will be hereafter described, and since any desired number of compartmentsmay be employed, a description of the elements in one cylinder compartment will, fully disclose the invention.

A rotar power shaft 3 extends through the cylin erand is located at the center thereof. An eccentric 4 lies between the flat side walls of the cylinder, and this eccentric is fixed to the rotary shaft 3. An annular piston P is mounted on the eccentric 4 and provided with flat side faces adapted to cooperate with the flatside walls 1 and 2 to prevent leaka e between the piston and said side walls. cylindrical pivot member 5, extending from the annular piston P, is embraced by a head of a rocker arm 7 ivotally supported by a rod or shaft 8. head 6 is equal in width to the iston P so as to cooperate with the flat wa s l and 2, thereby preventing direct communication between the intake chamber 9 and the-dis-- charge chamber 10.

Inlet and outlet ports 11 and 12, respectively, are formed at opposite sides of the head 6 to provide for the admission and discharge of fluid. The eccentric 4 turns with thepower shaft 3, as indicated by an arrow near the center of Fig. I, so a rotary -motion is imparted to the eccentric while the annular piston P. oscillates about the center of the pivotal connection 5. The piston P has a peculiar motion relative to the circular inner faceof the cylinder. When the parts occupy the position shown by p I dotted lines in ig. I, the piston P contacts with the circular cylinder face 13 at a point near the inlet port 11, and if a rotary motion is. imparted to the eccentric 4, the

point of contact between piston and cylinder will approach the outlet port 12. In response to a motionof this kinda body of fluidwill be drawn through the inlet port 11 and a body of fluid will be discharged through the outlet port 12. When the iston P reaches the position shown by 1111 lines in Fig. I, the last mentioned body of fluid will have been dischar d through the outlet port 12. A continue rotary motion of the eccentric will displace the piston P from a point of contact adjacent t e outlet port 12, asshown by dotted lines, and during this motion the piston is entirely free of'contact with the circular inner face 13 of the cylinder, and the fluid under pressure in the discharge chamber 10 will then tend to flow back into the cylinder. Since the piston P thus does not prevent free communication between the inlet and outlet ports during the period just referred to, I provide a simple automatic valve device which is effective during this period.

As an illustration of a suitable valve, I have shown a blade 15 pivotally interlocked with the piston and having a free edge adapted to engage the circular inner face of the cylinder. The circular outer face of the piston P is provided with a recess having side walls 16 and 17 which diverge from a cylindrical pocket 18 to the outer face of the piston, and the blade 15 is provided at its inner end with an enlarged cylindrical portion 19 closely fittedto the wall of pocket 18. The blade 15 is thus pivotally interlocked with the piston, and the axis of'this pivotal connection is parallel with the axis of shaft 3. The length of blade 15 is equal to the width of piston P, so the end edges of blade 15 will engage or lie very close to the flat side walls 1 and 2.

When the apparatus is used as a pump,

1 the valve blade 15 preferably extends from its pivotal connection to a point near the outlet port 12. This pivoted blade is exposed to the fluid pressure at the outlet port and it forms an automatic pressure actuated check valve, which prevents free communication between the outlet and inlet ports while the piston is moved from the position shown by full lines in Fig. I to the position shown by dotted lines. At the beginning of this movement, the fluid under pressure at the outlet port 12 will enter a small pocket 20, which may be formed by cutting away a portion of the free edge of the valve blade, and this fluid under pressure will then enter between the blade 15 and the wall 16 of the blade-receiving pocket, so as to force the blade into firm engagement with the circular inner .face of the cylinder. As the motion of the piston continues, the free outer edge of blade 15 Will remain in contact with the cylinder and the parts will eventually occupy the positions shown by dotted lines. Thereafter, the fluid in the crescenbshaped space between the piston and cylinder will be placed under pressure, and when this" pressure becomes greater than the fluid pressure at the outlet port 12, the valve blade 15 will be forced back into the recess between the diverging walls 16 and 17 so as to permit the outgoing liquid to escape through the outlet port 12 It will be understood that the valve device is closed by fluid pressure on its out-let side and that it remains closed until the piston again begins to force fluid through the outlet port.

Owing to the peculiar manner in which the piston is mounted, the free outer edge of the pivoted valve 15 will slide on the circular inner face of the cylinder, and even though this sliding motion resultsin slight wear of the valve or cylinder, the valve will continue to perform its function, for it is held in contact with the cylinder by fluid pressure and thereafter opened by the pressure of fluid on the inlet side of the valve. Furthermore, the valve blade does not strike hammer blows on the cylinder. The valve is held in a closed position by fluid pressure until it is opened by the pressure of the outgoing fluid on the inlet side of the valve.

\Vhen the blade 15 occupies the position shown by full lines in Fig. I, there is preferably a slightspace between said blade and the wall 16, the object being to provide a space for foreign matter which would otherwise tend to prevent the blade from occupying the position shown by full lines.

I claim:

1. The combination. of a cylinder, a piston in said cylinder, a rotary member on which said piston is ec-centrically mounted, said cylinder having inlet and outlet ports and said piston being movable from a point on the cylinder adjacent said outlet port to a point on the cylinder adjacent said inlet port, and a valve pivoted to said piston and adapted to contact with said cylinder while the piston is moving from one of said points to the other.

2. The combination of acylinder, a piston in said cylinder, a rotary member on which said piston is eccentrically mounted. said cylinder having inlet and outlet ports and said piston being movable from a point on the cylinder adjacent said outlet port to a point on the cylinder adjacent said inlet port, and a check valve whereby said outlet port is closed while the piston is moving from one of said points to the other. said check valve being pivoted to said piston and exposed to the fluid pressure at said outlet port so as to occupy its closed position in response. to said fluid pressure, and said pivoted check valve being movable to its open position in response to the pressure of fluid passing to said outlet port on the inlet side of the valve.

3. The combination of a cylinder, a piston in said cylinder, said iston being smaller in diameter than the internal diameter of said cylinder, a. rotary member on which said piston is eccentrically mounted so as to cooperate with the. circular inner face of said cylinder. a rocker-arm pivoted to the eocentrically mounted piston, said cylinder having inlet and outlet ports at opposite sides of said rocker-arm, said ecrentrically mounted piston being movable away from the inlet port and toward the outlet port to provide for the admission and discharge of fluid, said eccentrically mounted piston being also movable from a position adjacent said outlet port to a position adjacent said inlet port, and a valve pivoted to said piston and havingla free edge adapted to contact with said cylinder to close communication between said ports during the last mentioned movement of the piston.

4. The combination of a cylinder, a piston in said cylinder, said piston being smaller in diameter than the internal diameter of saidcylinder, a rotary member on which said piston is eccentrically mounted so as to cooperate with the circular inner face of said .cylinder, a'rocker-arm pivoted to the eccentrically mounted piston, said cylinder having inlet and outlet 'ports at opposite sides of said rocker-arm, said eccentrically mounted piston being movable away from the inlet port and toward the outlet port to provide for the admission and discharge of fluid, saideccentrically mounted piston being also movable from an extreme position adj acent said outlet port to an initial position adjacent said inlet port, and an automatic pressure actuated check valve whereby said outlet port is closed during the last mentioned movement of the piston, said check valve being pivoted to said piston and provided with a free edge adapted to contact with said cylinder, and said check valve being exposed to the fluid pressure on its outlet side.

5. The combination of a cylinder, a piston eccentrically mounted in said cylinder, a rocker-arm extending from said piston, said cylinder having inlet and outlet rts at opposite sides of said rocker-arm, sai piston having a circular outer face provided with a recess, and a pivotally mounted check valve located insaid recess and having a free outer edge movable into and out of engagement with said cylinder.

6. The combination of a cylinder, a piston in said cylinder, a rotary member on which said piston is eccentrically mounted, said cylinder having inlet and outlet ports and said piston being movable from a point on the cylinder adjacent said outlet port-to a point on the cylinder adjacent said inlet port, said piston having a circular outer face provided with a recess, and an automatic pressure actuated check valve .in said recess, said check valve comprising a blade pivotally interlocked with said piston and having a free outer edge adapted to engage said cylinder in response to pressure on one side of said blade.

7 The combination of a cylinder, a piston in said cylinder, a rotary member on which said piston is eccentrically mounted, said cylinder having inlet and outlet ports and said piston being movable from a point on the cylinder adjacent said outlet port to a point on the cylinder adjacent said inlet port, said piston having a circular outer face provided with a recess, and an automatic pressure actuated check valve in said recess, said check valve comprising a blade pivotally interlocked with said piston and having a free outer edge adapted to engage said cylinder in response to pressure on one side of said blade, the length of said blade being equal to the width of said piston and the axis of the blade pivot being parallel to the axis of said piston.

8. The combination of a cylinder, a piston eccentrically mounted in said cylinder, a rocker-arm extending from said piston, said cylinder having inlet and outlet ports at opposite sides of said rocker-arm, and a valve adapted to close one of said ports, said valve being interposed between said piston and cylinder and said valve being movable relative to the piston and cylinder, one of the last mentioned parts having a recess in which the interposed valve is normally seated, and a portion of said valve being separated from a wall of said recess 'to provide a space between said wall and valve.

9. The combination of a cylinder, a piston eccentrically mounted in said cylinder, a rocker-arm extending from said piston, said cylinder having inlet and outlet ports at opposite sides of said rocker-arm, said piston having a circular outer face provided with a recess, and a pivotally mounted check valve located in said recess and having a free'outer edge movable into and out of engagement with said cylinder, a portion of said valve being separated from a wall of said recess to provide a space between said wall and valve.

In testimony that I claim the foregoing I hereunto afiix my signature.

IRA B. HART. 

